Anatomy & Physiology 1 Exam 1

Anatomy

The study of the structures of the body and their relationships to each other, the oldest medical science (looking at a feature of the body and describing/understanding it in terms of its position, form, shape, and whether its connected to other features/organs)

Physiology

The study of the functions of the body parts and how they work to carry out their life-sustaining activities (what it does)

Compare and contrast anatomy and physiology

Anatomy dictates physiology and Physiology dictates anatomy (form and function go together)

Ex. Adaptations: Talons of an eagle are sharp (anatomy) so they can be used to kill prey (physiology)

Gross Anatomy

Studying anatomy without a microscope. Using dissections, we can study where organs are, relative to size, shape, and position

Microscopic Anatomy

Studying anatomy with a microscope. Using microscopic, we can study structures that are too small to see with the naked eye, like cells or tissues.

Molecular Physiology

Studying the function of individual molecules. Ex. Protein function is related to protein shape

Cellular Physiology

Studying the function of individual cellsS

Systemic Physiology

Studying the function of individual organ systems. Ex. A gastroenterologist studies the digestive system

Pathophysiology

Studying how diseases and aging alter physiology of organs and organ systems

Structural Organization

Atoms → Molecules → Organelle → Cells → Tissue → Organ → Organ System → Organism

Nine Characteristics of Life

1. Separation of external and internal environment is necessary (Ex. the plasma membrane separates cells from each other and from their environment, the skin seperates the body’s internal environment from the external environment)

2. Movement is necessary (Motility is when substances move through the body [cardiac and smooth muscle do this]; Locomotion is when whole body parts move [skeletal muscles do this])

3. Living things respond to stimuli (stimuli are changes in the internal or external environment; once they are detected, reactions occur to address them)

4. Digestion and absorption are necessary (Digestion is breaking down ingested substances, Once large molecules are broken down, small molecules can be absorbed)

5. Metabolism is necessary (Metabolism is the sum of all the chemical reactions that keep an organism: Catabolism - the reactions that break down large molecules, Anabolism - the reactions to build large molecules)

6. Excretion is necessary (Waste products like feces, urea, and CO2 must leave the body)

7. Growth and repair are necessary (Growth is an increase in the size or number of cells)

8. Reproduction is necessary (Reproduction is the production of offspring, *not vital to individual organisms to reproduce, *is vital for species to reproduce)

9. Homeostasis (Maintenance of stable internal conditions, the central principle of physiology)

Homeostasis

• A relatively constant set of internal conditions that stay the same even when external conditions change

  • Homeostasis is dynamic, meaning it changes to keep things in balance

  • All the body’s organ systems work together to maintain homeostasis

• Homeostasis is maintained using negative and positive feedback loops

Negative Feedback Loops

• Goal: to get the body back to the original set point as quickly as possible

  • The response reduces (or completely cancels) the impact

  • Examples: thermoregulation (body temperature), chemical balance (pH or blood salinity), hormone levels (insulin and glucagon)

Positive Feedback Loops

• Goal: to create a “new temporary set point”

  • The response increases the effect of the stimulus

  • Positive feedback loops control things that are NOT constantly being adjusted

  • Examples: blood clotting, labor and delivery, neuron signaling

Organ System Functions

1. Integumentary - The external body covering that makes Vitamin D and has receptors and glands

2. Muscular - The system that enables movement, maintains posture, and generates heat

3. Skeletal - The system that protects and supports organs and provides a framework for muscle attachment

4. Nervous - The control system that responds to internal and external stimuli

5. Cardiovascular - The system that pumps blood (with oxygen, carbon dioxide, nutrients, and waste)

6. Lymphatic - The system that collects fluid from tissues and houses white blood cells

7. Respiratory - The system that supplies oxygen to the blood and removes carbon dioxide

8. Endocrine - The glands that secrete hormones to regulate growth, reproduction, and metabolism

9. Digestive - The system that breaks down food into absorbable units (that enter the bloodstream) and eliminates waste

10. Urinary - The system that regulates water, electrolyte, and acid-base balance in the blood

11. Reproductive - The system that is used to generate offspring

Body Cavity

• All of the body’s organs are found inside cavities

  • Cavities provide protection to the organs inside them

• Cavities can be open or closed

Open Cavities

• The oral cavity

• The digestive cavity

• The nasal cavity

• The orbital cavity

• The external ear

Closed Cavities

• Dorsal Body Cavity (Cranial Cavity + Vertebral Cavity)

• Thoracic Cavity (Superior mediastinum, Pleural cavity, Pericardial)

• Abdominopelvic Cavity (Abdominal Cavity + Pelvic Cavity)

• Ventral Body Cavity (Both Thoracic and Abdominopelvic Cavities)

Major Right Upper Quadrant (RUQ) Organs

Liver (right portion)

Gallbladder

Duodenum (first part of the small intestine)

Pancreas (head)

Right kidney and right adrenal gland

Major Left Upper Quadrant (LUQ) Organs

Stomach

Spleen

Left kidney and left adrenal gland

Pancreas (body and tail)

Liver (left portion)

Major Right Lower Quadrant (RLQ) Organs

Appendix

Cecum (first part of the large intestine)

Right ureter

Right reproductive organs (right ovary and fallopian tube)

Major Left Lower Quadrant (LLQ) Organs

Descending and sigmoid colon

Left ureter

Left reproductive organs (left ovary and fallopian tube)

Regional Terms

• Cephalic (Head)

  • Fronta

  • Orbital

  • Nasal

  • Oral

  • Mental

• Cervical (throat)

• Thoracic (chest)

  • Sternal

  • Axillary

  • Mammary

• Abdominal

  • Umbilical

• Pelvic

  • Inguinal (groin)

• Pubic (genital

• Upper Limb

• Manus (Hand)

• Lower Limb

• Pedal (foot)

• Cephalic

  • Otic

  • Occipital (back of the head)

• Back (dorsal)

  • Scapular

• Vertebral

• Lumbar

• Sacral

• Gluteal

• Perineal

Anatomical Position

• Body is erect

• Palms facing forward

• Feet slightly separated

Superior

above

Inferior

below

Lateral

away from the midline

Medial

closer to the midline

Proximal

closer to the attachment point (arms and legs)

Distal

farther from the attachment point (arms and legs)

Anterior

closer to the front

Posterior

closer to the back

Ventral

closer to the front

Dorsal

closer to the back

Prone

laying facing down

Supine

laying face up

Right Lateral Recumbent

lying on right side

Left Lateral Recumbent

lying on left side

Midsagittal (medial) Plane

Divides the body into right and left sections

Frontal (coronal) Plane

divides the body into anterior (front) and posterior (back) sections

Transverse Plane

divides the body into superior (top) and inferior (bottom) sections

Tissue

a group of cells (and extracellular materials) that have similar structures (anatomy) and similar functions (physiology)

Epithelial Tissue

found on external surface and internal cavities, prevents leakage from one cavity to another, protects, secretes, absorbs, and filters. Contains Lining of digestive tract organs and other hollow organs, glands (e.g., pancreas), and skin surface (epidermis)

Connective Tissue

supports, protects, and binds other tissues together. Contains bones, tendons, fat, and other soft padding tissue

Muscle Tissue

cells that contract and cause movement. Contains muscles attached to bones (skeletal), heart (cardiac), and walls of hollow organs (smooth)

Nervous Tissue

receives, processes, and transmits messages (internal communication). Contains brain, spinal cord, and nerves

Functions of epithelial tissue

• Protection - against microorganisms, UV light, mechanical damage

• Absorption - transmission of molecules into cells

• Filtration - separation of materials

• Excretion - elimination of waste materials

• Secretion - movement of substances

  • Sensory Reception - detection of changes in external environment

Epithelial cell shapes

• Squamous = flat or “squashed”

• Cuboidal = cube-shaped

• Columnar = column-shaped

Epithelial cell layers

• Simple = 1 layer

• Stratified = more than 1 layer

• Pseudostratified = 1 layer, but appears to be many

• Transitional = several layers

Characteristics of epithelial tissue

• Epithelial tissue has apical-basal polarity

  • the apical surface (“top”) is exposed to the outside

  • the basal surface (“bottom”) is attached to lower tissue layers (e.g., basement membrane)

T or F: Epithelial tissue is always on top of connective tissue

True

T or F: Epithelial tissue is avascular (no blood vessels).

True

Tight junctions

Form a leak-proof barrier between neighboring epithelial cells (found in areas where extracellular fluids need to be kept separate, like the blood-brain barrier)

Adherens junctions

Indirectly link cell cytoskeletons to provide strong connections

Gap junctions

Provide a direct channel between neighboring epithelial cells (so they can have a shared chemical environment)

Desmosomes

Provide structural reinforcement between epithelial cells in areas that stretch

Hemidesmosomes

Anchor epithelial cells to underlying connective tissue

Simple Squamous Epithelium

• Locations:

  • Lining capillaries (small blood vessels)

  • Alveoli (air sacs)

  • Glomeruli (kidney blood vessels)

  • The mesothelium (around abdominopelvic organs)

• Functions:

  • Allowing diffusion and absorption

Simple Cuboidal Epithelium

• Locations:

  • Kidney tubules

  • Ducts of glands

  • Ovaries

  • Seminiferous tubules

• Functions:

  • Secretion

  • Absorption

Simple Columnar Epithelium

• Locations:

  • Non-ciliated: the digestive tract, ducts of glands

  • Ciliated: the uterus, the oviducts

• Functions:

  • Non-ciliated: secretion and absorption

  • Ciliated: movement

Pseudostratified Columnar Epithelium

• Locations:

  • Upper respiratory tract

  • Reproductive system (e.g., vas deferens, epididymis)

• Functions:

  • Secretion

  • Movement

Stratified Squamous Epithelium

• Locations:

  • Keratinized (hard, structural protein): skin

  • Non-keratinized: mouth, vagina, rectum

• Functions:

  • Protection from abrasion (friction)

Stratified Cuboidal Epithelium

• Locations:

  • Salivary glands

  • Sweat glands

  • Mammary glands

• Functions:

  • Secretion

  • Strengthens glands

Stratified Columnar Epithelium

• Locations:

  • Pharynx (throat)

  • Urethra (urinary tract)

  • The conjunctiva (white of eye)

• Functions:

  • Protection

  • Secretion

Transitional Epithelium

• Locations:

  • Urinary bladder

• Functions:

  • Stretching

  • Protection from urine

Endocrine Glands

Secrete into the bloodstream (hormones)

Exocrine Glands

Excrete out of the body or an organ (sweat, saliva, mucus, digestive enzymes) via ducts

Extracellular Matrix (ECM)

Surrounding material that supoorts the cell

Connective Tissue Components - Fibers

• Collagen Fibers → thick fibers that are very strong

• Elastic Fibers → thin, stretchable fibers

• Reticular Fibers → delicate, net-like fibers

Connective Tissue Cells

• -blast cells are immature (still building ground substance and proteins)

• -cyte cells are mature (can only maintain the existing matrix)

• Fibroblasts → fiber-building cells in many connective tissues

• Chondrocytes → mature cartilage cells

• Osteocytes → mature bone cells

• Erythrocytes and Leukocytes → mature blood cells

Types of Connective Tissue

General Functions of Connective Tissue

• Binding

  • Areolar loose connective tissue

  • Dense regular connective tissue

  • Dense irregular connective tissue

• Protection

  • Bone tissue

  • Blood

  • Adipose tissue

• Energy storage

  • Adipose tissue

  • Bone

• Support

  • Bone

  • Hyaline cartilage

  • Elastic cartilage

  • Fibrocartilage

• Insulation

  • Adipose tissue

• Transport

  • Blood

  • Dense elastic connective tissue

Areloar Connective Tissue

• Important Features

  • All three fiber types are seen in this tissue

  • Fibroblasts (fiber-building cells) and leukocytes (white blood cells) are visible

• Location

  • Surrounding organs

  • Below the epithelium

• Function

  • Wraps and cushions organs

  • Retains extracellular fluid

Adipose Connective Tissue

• Adipose tissue (fat) is made of adipocytes

  • Their nucleus is pushed to the side of the cell

• Locations

  • Abdominal cavity

  • Under skin

  • Breasts

• Functions

  • Lipid storage

  • Protection

  • Insulation

Reticular Connective Tissue

• Reticular connective tissue only has reticular (net-like) fibers

• Location

  • Lymph nodes

  • The spleen

  • Liver

  • Bone marrow

• Functions

  • Supports red and white blood cells

  • Assists in filtration

Dense Regular Connective Tissue

• The many collagen fibers in this tissue are arranged regularly (fibroblasts are squished flat in between the fibers)

• Location

  • Tendons (attach muscle to bones, “thick rubber band”)

  • Ligaments (attach bone to bone)

  • Aponeuroses (attach muscle to bone, “thin sheet”)

• Function

  • Strong attachment for bones and muscle

  • Withstands pulling in one direction

Dense Irregular Connective Tissue

• The many collagen fibers in this tissue are arranged irregularly (the collagen fibers are also thicker than in dense regular)

• Location

  • The reticular layer of the dermis

  • Capsules around joints and organs

• Function

  • Withstands pulling in multiple directions

Dense Elastic Connective Tissue

• Elastic fibers that appear dark purple when stained

• Location

  • Walls of large arteries

  • Walls of the bronchiole tubes in the lungs

• Function

  • Stretching and recoiling (like a rubber band)

Cartilage

• Three types

  • Hyaline

  • Elastic

  • Fibrocartilage

• Functions

  • Strong and flexible to protect joints

  • Helps keep joint shape when moving

  • Absorbs shock

• Anatomical features

  • Tough, dense flexible matrix

  • Chondrocytes - sparsely distributed cells in lacunae

  • Surrounded by perichondrium - dense irregular connective tissue

Hyaline Cartilage

• This is the most abundant cartilage in the body

  • the cells are called chondrocytes, found in lacuna (“little house” or bubble), appears “glass-like”

• Location

  • The fetal skeleton

  • Some joints

  • Nose

• Function

  • Template for bone

  • Support and reinforcement

Elastic Cartilage

• Location

  • External ear

  • Epiglottis (prevents choking)

• Function

  • Maintains shape

  • Allows flexibility

Fibrocartilage

• Has thick collagen fibers that are visible, stain blue on slides

• Location

  • Intervertebral discs of the spine

  • Knee

  • Temporomandibular joint

• Function

  • Strong support

  • Absorbing shock

Compact Bone

• The ECM of bone contains calcium phosphate + collagen

• Location

  • The outside of bones

• Function

  • Support and protection

  • Muscle attachment site

  • Calcium storage

Spongy Bone

• Spongy bone has trabeculae (little columns that distribute force)

• Location

  • Beneath compact bone

• Function

  • Hematopoiesis (making red blood cells)

  • Fat storage

Cutaneous membrane

The skin

Mucous membrane

Cavities open to the environment

Serous membrane

On organs in the ventral body cavities

Integument

The skin or cutaneous membrane is the barrier between the internal and external environments

Major functions of the integument

• Barrier to environmental microbes

• Prevents water loss

• Thermoregulation

• Detecting sensation

• Vitamin D synthesis

• Excretion

Layers of the skin

• Epidermis

  • Keratinized stratified squamous epithelium

• Dermis

  • Papillary layer of the dermis

    • Areolar loose connective tissue

  • Reticular layer of the dermis

    • Dense irregular connective tissue

• Subcutaneous (hypodermis)

  • Adipose loose connective tissue

Layers of the Epidermis (in order from top to bottom)

• Stratum corneum

• Stratum lucidum (only present on the palms of hands and soles of feet)

• Stratum granulosum

• Stratum spinosum

• Stratum basale

Stratum basale

• The deepest layer of the epidermis, closest to the dermis

• Includes melanocytes (produces melanin) and Merkel cells (tactile cells) stimulates the Merkel disc (sensory nerve cell)

Stratum spinosum

• Keratinocytes in this layer have spiny cell junctions

• Desmosomes strongly attach these cells to one another

• Langerhans cells and melanin granules are also in this layer

• Most abundant (thickest) layer of living cells

Stratum granulosum

• The dark spots in this layer are lamellar granules

  • Function: prevents water loss from the skin

• Cells start to keratinize here

• Cells begin to die in the upper region of this layer

Stratum corneum

• This is the outermost layer of dead/non-living cells

• Increased keratinization provides protection against abrasion and microbes

• These cells are constantly being shed, generating replacement

Stratum lucidum (clear layer)

• Only seen in thick skin

  • It is superficial to (closer to body surface) stratum granulosum

  • It is deep to (farther away from body surface) stratum corneum

• Thick skin is present on the palms of the hands and the soles of the feet

  • It does not have sebaceous (oil) glands or hair

Cells of the Epidermis

• Keratinocytes are the most abundant cell type

  • Function: replenish epithelium and make keratin

  • Keratinocytes on the outer skin surface (corneum) are dead

• Langerhans cells are the “immune system” of the epidermis

  • Function: phagocytose foreign substances

  • These cells migrate to the epidermis from the red bone marrow

• Melanocytes are the melanin-producing cells

  • Darkens skin

  • Function: protecting the skin from UV radiation

  • Melanin is stored in melanosomes which are transferred to keratinocytes

• Merkel cells are rare

  • Function: detecting touch and proprioception (spatial position)

  • Interacts with the Merkel disc in the underlying dermis (a sensory nerve cell)

Skin Pigments

• Melanin is a reddish-yellow/brownish-black pigment

  • Made by melanocytes in the epidermis

  • Everyone has the same number of melanocytes, but not the same amount of melanin

• Exposure to UV radiation stimulates the activity of melanocytes

• Carotene is a yellow/orange pigment obtained from plants

  • Carotene is used to make Vitamin A (retinol)

  • It can accumulate in stratum corneum

• Hemoglobin leads to red/pink color

  • It is found in red blood cells of the dermis

  • When melanin levels are low, hemoglobin’s color is more visible

  • Blushing is due to vasodilation

Alterations to skin color

• Erythema: redness due to increased blood

• Pallor: paleness due to decreased blood

• Bruising: changing color to pooling blood under skin

• Albinism: melanocytes unable to produce melanin

• Cyanosis: blueness due to low oxygenated blood

• Jaundice: yellowing due to liver malfunction

• Vitiligo: certain areas lose ability to produce melanin

• Addison’s Disease: bronze patches due to adrenal gland malfunction

Papillary Layer of the dermis

• Attached to the epidermis

• Dermal papillae are ridges with collagen fibers and nervous structures

  • The pattern of these ridges determine a person’s fingerprint

    • Fingerprints = “friction ridges”

  • Fingerprints assist with grip and the sense of touch